Transcript Ad_Hominem_and_Guilt_by_Associaton_4.14.09_gRANT_fISHER

Ad Hominem
Or argumentum ad hominem
Definition

Also known as, argument to the man, Ad
Hominem is “…a general category of fallacies
in which a claim or argument is rejected on the
basis of some irrelevant fact about the author of
or the person presenting the claim or argument.”
Examples
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Person A makes claim X.
Person B makes an attack on claim X for a flaw.
Therefore A's claim is completely false.
Bill: "I believe that abortion is morally wrong."
Dave: "Of course you would say that, you're a priest."
Bill: "What about the arguments I gave to support my
position?"
Dave: "Those don't count. Like I said, you're a priest,
so you have to say that abortion is wrong. Further, you
are just a lackey to the Pope, so I can't believe what you
say."
Examples
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A prosecutor asks the judge to not admit the
testimony of a burglar because burglars are not
trustworthy.

Francis Bacon's philosophy should be dismissed
since Bacon was removed from his
chancellorship for dishonesty.
How To Avoid this Fallacy

Get more proof that the claim is wrong and
then it wont be a fallacy.
Guilt by association
Definition
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Guilt by association can be described as,
“…(an) argument (that) attacks a source because
of the similarity between the views of someone
making an argument and other proponents of
the argument.”
Examples
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Source A makes claim P.
Group B also make claim P.
Therefore, source A is a member of group B.
Also
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Source A makes claim P.
Group B make claims P and Q
Therefore, Source A makes claim Q.
Examples
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"You say the gap between the rich and poor is
unacceptable, but communists also say this, and therefore
you are a communist. Communists are unlikeable, and
therefore everything they say is false, and therefore
everything you say is false.“
You say that Jamaicans smoke marijuana,
Jamaicans are from the Caribbean. So all
Caribbean people smoke marijuana.
How To Avoid this Fallacy

Since these two fallacies are almost exactly the
same the have the same solution. Get more
proof that the claim is wrong and then it wont
be a fallacy.
Activity
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Have a class discuss on real life applications of
the previous fallacies.
Source Cited
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Hurley, Patrick (2000). A Concise Introduction to Logic,
Seventh Edition. wadsworth, a division of Thompson
Learning. pp. 125–128, 182. ISBN 0534520065.
"Fallacy: Ad Hominem." Holocaust Educational
Resource. 2009. 13 Apr. 2009
<http://www.nizkor.org/features/fallacies/adhominem.html>.
"Argumentum Ad Hominem." Philosophy Home Page.
13 Apr. 2009
<http://philosophy.lander.edu/logic/person.html>.